For an "NPC" game, there's actually a surprising amount of polish.
The story is alright; there's not really much to say about it. The dialogue has some entertaining moments.
The real focus is (and should be) the sex scenes, which are well drawn with smooth animations and sounds that actually fit what's going on (rather than stock sex sounds).
In addition to the standard 'fuck the npc while they have their general dialogue and blank stare', each character has a secondary sex scene in which they do react to the player.
If you're going to give any of the NPC games a try, this would be the one that's worth it. The game takes only about 20 minutes to complete, depending on how much time you spend with the scenes.